The environmental catastrophe unfolding around us isn’t news (the plankton’s appearance coincided with a report that carbon dioxide levels had just risen at a record rate for the second year running, despite global efforts to curb emissions). Yet its uncanny beauty offered a reminder of something that is less often discussed – the degree to which environmental change destabilises not just our physical world, but also our psychic world, dislocating us from the places and rhythms that we know and rendering the familiar strange, even disturbing.

Missy Higgins: how an obsession with apocalyptic climate fiction changed my life

Read more

It’s not necessary to dig too deep to understand why such events might unsettle us. The writer Jeff VanderMeer has described climate change as a kind of haunting. Drawing upon the philosopher Timothy Morton’s notion of climate change as a sort of hyperobject, a thing so large as to be ungraspable in its totality. VanderMeer suggests the emotional unsettlement induced by climate change is a result of our sense that the natural order is being violated. The boundary between what we perceive as reality, and the unsettled, terrifying world beyond it becomes permeable.

In a similar vein, the late Mark Fisher drew a distinction between the weird and the eerie, arguing that the weird involves the intrusion into the everyday of “that which does not belong”, while the eerie involves the disruption of our assumptions about agency, granting presence and purpose to places and things and stripping it from humans and animals. When Fisher directs our attention to the flocking birds in Daphne du Maurier’s eponymous short story, or the featureless yet frighteningly present landscapes of MR James’ fiction (also memorably discussed in Robert Macfarlane’s essay on the eeriness of the English countryside), it is difficult not to be reminded of the way climate change intrudes into our understanding of the world, emptying landscapes and deranging the behaviour of animals.

Australian author James Bradley: ‘Environmental change destabilises not just our physical world, but also our psychic world.’

These sorts of ideas were very much on my mind across the summer of 2013/2014. Although it would be a year until it was published, I had just finished writing my novel, Clade, which sought to capture something of the disruption and convulsion of the coming century through the experiences of a single family.

People sometimes describe Clade as a hopeful book, but I’ve never been sure that’s quite right. For while it deliberately resists the seductions of despair, emphasising instead contingency and the depth of time ahead of us as well as behind, it is still a book that is suffused with grief.

Yet as that abnormally long, abnormally hot summer stretched on, I found myself imagining a different kind of book, one in which the worst had already happened. As is often the case with my work, the story really began with an image: that of a girl and her sister making their way through a flooded landscape, in which all traces of our world had been washed away, replaced instead by crowding rainforest. I didn’t know who they were, or where they were going, but I knew them. The bond between them; the older girl’s determination to protect her sister. And – perhaps just as importantly – I knew the landscape they were travelling was both ours and not, its alien strangeness a reflection of a world in which the environment had begun to metamorphose into something alien and uncanny.

As I wrote The Silent Invasion, other pieces began to fall into place: the arrival of something alien on Earth; widespread panic and the battle for control; the idea of replication and the uncanny. And perhaps most importantly, the idea of a natural world that was no longer passive, but connected, sentient, its mind distributed not just through animals and humans, but plants, bacteria, all living things.

I also realised I was writing a kind of book I hadn’t written before, one aimed as much at younger readers as at adults. The notion that I might write something for teenagers had been at the back of my mind for a while, partly because having kids of my own had led me back to the books I loved when growing up.

There was something liberating about this realisation, and the emotional and narrative directness it demanded of me. But as I followed my characters deeper into the altered world of the novel, I began to understand the decision to write for younger readers also mattered because it is younger people who will inherit the world we are making.

Through it all though the idea of this alien intelligence – the Change – possessed me, as did the idea that those absorbed into it were altered, transformed into something blank, indifferent, other. In it, I saw something of the strangeness and haunting we increasingly feel when we look at the world around us. I saw something of the ways in which climate change is altering our ideas about agency, forcing us to grapple not just with the idea of landscapes as a whole but with the interconnectedness of all things.